1. Technical Field
The present invention relates an optical head having a plurality of light emitting portions and an electronic device.
2. Related Art
Image forming apparatuses such as a printer have an optical head for exposing an image carrier (for example, a photoconductor drum) and for writing a latent image thereon. Such a kind of optical head has a light emitting element array in which many light emitting elements are arranged in the main scanning direction. Further, the light emitting element array is configured such that a plurality of light emitting element chips, in which a predetermined number of light emitting elements is arranged, are lined up in the main scanning direction.
However, when a plurality of light emitting element chips are lined up in a line in the main scanning direction, in order to keep the light emission pitch constant even at the boundary portion between the neighboring light emitting element chips, it is necessary to set the distance from the endmost light emitting element to the chip end portion to a half or less of the light emission pitch in each light emitting element. However, when the distance from the endmost light emitting element to the chip end portion is set to be equal to or less than a half of the light emission pitch, if the light emission pitch is set to be small in order to increase the resolution thereof, a problem arises in that the endmost light emitting element may be dropped out when the light emitting element chips are cut, or the like. Hence, there is provided a technique for arranging the plurality of light emitting element chips in a staggered manner in the main scanning direction (for example, refer to JP-A-2002-248803 and JP-A-2008-155458).
However, when the plurality of light emitting element chips are arranged in a staggered manner in the main scanning direction, the width of the optical head in the sub-scanning direction increases.